A Failure Probability Analysis of a Modular Algorithm to Compute the Monic GCD of Multivariate Polynomials over Algebraic Number Fields \({\mathbb {Q}(\alpha _1,\ldots ,\alpha _n)}\)
摘要
Let \({\mathbb {Q}(\alpha _1,\ldots ,\alpha _n)}\) be an algebraic number field. In 2023, Ansari and Monagan designed a modular algorithm to compute the monic gcd g of two polynomials \(f_1\) and \(f_2\) in \({\mathbb {Q}(\alpha _1,\ldots ,\alpha _n)}[x_1,\ldots ,x_k]\) . The algorithm computes g modulo primes and uses interpolation to recover \(x_2,x_3,\dots ,x_k\) in g. However, the algorithm may fail in certain cases, for instance, when encountering a zero divisor. In this paper, we present a refined classification of failure cases for this algorithm and provide a detailed analysis of their probabilities.